(CNN) – Senate Democrats are expecting their colleague Sen. Tim Johnson to announce his retirement at an event in his home state of South Dakota Tuesday, according to a senior Democratic congressional source.

The event is scheduled to take place at Johnson's alma mater, the University of South Dakota. A press release said the event would be "regarding the 2014 election."FULL POST

(CNN) - Former presidential nominee and Sen. George McGovern has been admitted to a hospice in Sioux Falls, South Dakota, a spokeswoman for the facility said Monday.

"The family of Sen. McGovern wishes to extend their gratitude and appreciation for the many prayers and well wishes and requests complete privacy at this time," said Lindsey Meyers, spokeswoman for Avera McKennan Hospital and University Health Center.

Washington (CNN) – Presumptive GOP presidential nominee Mitt Romney picked up more ammo in his quest for the White House, sweeping primaries in Montana, New Jersey, New Mexico, South Dakota and California on Tuesday night.

Though he had already won enough delegates - 1,144 - to clinch the Republican presidential nomination by last week, Romney technically remains the presumptive nominee until the party's convention in August.

Editor's Note: In the final 100 days before Election Day, CNN has been profiling one race at random each day from among the nation's top 100 House races, which we've dubbed "The CNN 100." Read the full list here. Today's featured district is:South Dakota At-Large – Rep. Stephanie Herseth Sandlin (D) is seeking a 4th full term
Primary: June 8, 2010
Location: All of South Dakota
Days until the election: 25

Democrat Rep. Stephanie Herseth Sandlin has been touting her independent streak, but even her votes against some of her party's major legislative efforts might not be enough to fend off her Republican challenger this November.FULL POST